Climate Science Glossary

Term Lookup

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Term:

Settings

Beginner Intermediate Advanced No DefinitionsDefinition Life:

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 29 January 2018 by dana1981

Over the past decade, coal has been increasingly replaced by cheaper, cleaner energy sources. US coal power production has dropped by 44% (866 terawatt-hours [TWh]). It’s been replaced by natural gas (up 45%, or 400 TWh), renewables (up 260%, or 200 TWh), and increased efficiency (the US uses 9%, or 371 TWh less electricity than a decade ago).

Evolution of the American power grid mix since 1960. Illustration: Carbon Brief

In other words, of the 866 TWh of lost coal power production, 46% was picked up by natural gas, 43% by increased efficiency, and 23% by renewables.

Natural gas is an unstable ‘bridge fuel’

While the shift away from coal is a positive development in slowing global warming by cutting carbon pollution, as Joe Romm has detailed for Climate Progress, research indicates that shifting to natural gas squanders most of those gains. For example, a 2014 study published in Environmental Research Letters found that when natural gas production is abundant, it crowds out both coal and renewables, resulting in little if any climate benefit. Part of the problem is significant methane leakage from natural gas drilling.

...abundant gas consistently results in both less coal and renewable energy use […] the quantity of methane leaked may ultimately determine whether the overall effect is to slightly reduce or actually increase cumulative emissions […] only climate policies bring about a significant reduction in future emissions from US electricity generation … We conclude that increased natural gas use for electricity will not substantially reduce US GHG emissions, and by delaying deployment of renewable energy technologies, may actually exacerbate the climate change problem in the long term.

Similarly, another 2014 study found that based on the latest estimates of methane leakage rates from natural gas drilling, replacing coal with natural gas provides little in the way of climate benefits. Though it’s been touted as a ‘bridge fuel’ to span the gap between coal and renewables, this research suggests natural gas isn’t significantly better than coal in terms of global warming effects, and thus may not be suitable for that purpose. The ‘bridge’ doesn’t appear to achieve its goal of steadily cutting our greenhouse gas emissions.

Renewables and batteries are starting to beat natural gas

California has been a national leader in clean energy. The state generates very little of its electricity from coal, but natural gas does supply more than a third of the state’s power. A quarter is generated by renewable sources like wind, solar, and geothermal plants, and another 10% comes from hydroelectric dams, on average. In 2017, renewables’ share increased by about 10%, displacing natural gas in the process.

In fact, California has an excess of natural gas power generation capabilities. Some natural gas plants are still essential for ensuring local grid reliability, but in many cases, clean energy resources like a combination of solar and storage can meet reliability needs.

In one recent example, the California Public Utilities Commission (CPUC) ordered Pacific Gas & Electric (PG&E) to procure energy storage (batteries) or “preferred resources” (renewables or increased efficiency and conservation) to meet a local reliability need in northern California. The order stemmed from an issue with a “peaker” natural gas plant (so-called because they switch on to meet high, peak electricity demand) operated in northern California. The operator (Calpine) was concerned that the plant was no longer economical, because it’s too infrequently used due largely to an abundance of renewable power. The contract they could receive for providing generation capacity to ensure grid reliability would not be high enough to cover costs to maintain the plant.

Instead of bidding their plant into the program overseen by the CPUC to ensure local reliability, Calpine went directly to the California Independent System Operator (CAISO) and requested a “reliability must-run resource” contract, which is a much higher payment than they would have received through the CPUC program. CPUC decided instead to require PG&E to fill the local reliability need with cleaner alternatives. The costs of renewable energy and battery storage have fallen so fast that the clean alternatives might now be cheaper than gas.

The redundancy and potential replacement of natural gas with cleaner alternatives extends far beyond these examples. Most electrical service providers in California are now required to develop integrated resource plans. These are electric grid planning documents that outline how the utilities will meet a number of California’s goals, including a 40% reduction in carbon pollution below 1990 levels and 50% electricity production from renewable sources by 2030. Meeting these goals will require replacing non-critical natural gas plants with renewable power.

Comments

If I heard the announcement correctly, in Australia, the government is going to give solar panels and batteries to 50,000 homes to mitigate the effects of turning on air conditioners during heat waves. Essentially they are building a new diffuse power station. Their heat waves are getting ever more severe and cause brown outs as people try to keep cool enough to survive.

I'm sorry to have to write this, folks, but the problem is not the annual rate of CO2 emissions. It is the accumulated sum of all CO2 emissions since Watt perfected the steam engine, or since people started using coal to keep warm in winter.So a global switch from coal to something that cuts the emissions rate in half (presuming that the methane released does NOT wipe out the improvement) only reduces by half the rate at which the problem is worsening.The fact that gas turbine backup is essential nearly everywhere that the wind and solar "renewables" are installed, explains why Germany's Energiewende has predictably failed to improve Germany's CO2 emissions. The worst part of it, unless you have a financial interest in fossil carbon, was the choice of nuclear power to be replaced.

The logic of Industrial Oceanic Warming and Acidification demands that as soon as possible, we reduce the role of fossil carbon to that of horse-drawn carriages, and then find a way to recapture the carbon dioxide from the seas and the air.Dr. Alex Cannara, in a presentation about OceanAcidification , goes into this topic.

It boggles my mind that California's liberals are so hostile — with the exception of people like Michael Shellenberger — to nuclear. I am also a hardcore liberal and lifelong environmentalist, and have been an American citizen since the reign of Gerald the Pardoner.When I was still a British subject, I admired the USA that it could have three of the first four elements to follow those named after the gods Uranus, Neptune, and Pluto, be named after America, Berkeley, and California. Yes, I studied nuclear physics.I have done enough of the arithmetic to be convinced that solar panels even with batteries are a pathetic approach compared with nuclear research done in the USA on Molten Salt Reactors and the Integral Fast-neutron Reactor, even before the infamous and wildly exaggerated Chernobyl recklessness and stupidity.Also, having lived ten years in Scotland and fourteen in Northern Ireland, it is evident to me that sunshine is not the key to world wide solution of the global warming problem.

I see that you have no peer reviewed material to share with us to support your wild claim that nuclear is required to reduce fossil CO2 emissions. It is sloganeering to continue to make unsupported claims.

Of course current renewables require backup at this time. It is still extremely early days for renewable energy. As more renewable energy is built out, non-fossil storage will be built. It is like the argument that cars can never replace horses because there are no gas stations.

Try to post all your wild claims about nuclear on the same thread so that everyone can follow them. When you make the same claims on multiple threads it is difficult to respond.

00

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.